The present invention relates to an opening and closing device for a cassette holder or the like in a cassette tape recorder.
It has heretobefore been proposed to provide a cassette holder mounted in a cassette tape recorder which is constructed such that when closing a cassette holder in which a cassette has been inserted, the cassette is ready to be played, while after completion of playing it is removed from the cassette holder by depressing an ejection push button.
FIG. 1 and FIG. 2 illustrate an example of the hitherto known cassette holder which is constructed in the above-mentioned manner. As shown in the drawings, a cassette holder 2 is mounted in an opening 1a of a front pannel 1 of the tape recorder in such a manner that the cassette holder can be tilted about the lower portion thereof as a center of rotation. On the upper part of the cassette holder 2 there is provided a swing lever 4 which is arranged rotatably around a pin 3 on the holder 2. Further a lift lever 8 to be actuated by the ejection button 7 is arranged vertically displaceably with the aid of pins 6 secured to a chassis 5 and elongated holes 9 through which the pins 6 extend. The swing lever 4 extends through an insert hole 11 in the side wall 10 of the casing of the device in such a manner that the lower surface thereof comes in sliding contact with the top end of the lift lever 8. Further the swing lever 4 is provided with an engagement recess 12 on the lower surface thereof, with which the lower edge of the side wall 10 in the insert hole 11 comes in engagement. It is to be noted that the cassette holder 2 is always biased in the opening direction with the aid of a spring 13, while the swing lever 4 is always biased in the counterclockwise direction by means of spring 14.
When the cassette holder 2 is kept closed, as shown in FIG. 1, the swing lever 4 is engaged at its recess 12 to the lower edge of the side wall 10 in the insert aperture 11, which prevents the cassette holder 2 from being opened by means of spring force of the spring 13. When it is desired to open the cassette holder 2, the ejecting button 7 is depressed, causing the lift lever 8 to be raised. As the lift lever is raised, the swing lever 4 is rotated around the pin 3 as a center of rotation in the clockwise direction, till the recess 12 is disengaged from the lower edge of the said insert hole 11. As a result the cassette holder 2 is opened by means of the spring 13, as shown in FIG. 2. Now the cassette is ready to be removed.
It is pointed out, however, that known opening and closing device for a cassette holder as discussed above has drawbacks. The cassette holder is very quickly opened with accompanying shock due to the arrangement that the cassette holder 2 is opened with the aid of spring force of the spring 13. Shock noises are generated during opening operation of the cassette holder 2. Also, the opening operation is performed without the desired sensitivity control. In order to eliminate the above-described drawbacks, it is conceivable to reduce the spring force for opening the cassette holder. With the device constructed in this way, however, another drawback is that the cassette holder fails to ensure sufficiently high opening force. Further due to the arrangement that the spring 13 for opening the cassette holder 2 and the spring 14 serving to hold the cassette holder 2 in the closed state are separately provided, the known device has a drawback that it requires additional component parts. Moreover because it is difficult to set the spring force of the springs 13 and 14 to the required magnitude, another drawback is that the cassette holder fails to be smoothly opened and closed, when the spring force is not in appropriate relative magnitude.